Recent questions and answers in Classification and Structure of Materials

The equilibrium vacancy concentration in aluminum at $900$ $\mathrm{K}$ is $1.1 \times 10^{-4}$. The enthalpy of formation of vacancies in $\mathrm{kJ}. \mathrm{mol}^{-1}...

In a cubic crystal, the Burgers vector for a mixed dislocation line is $\dfrac{a}{2}$ $[110]$. The dislocation line lies along the $[011]$ direction. The slip plane of th...

Which one of the following statements regarding point defects in ionic solids is correct?Frenkel defects are dominant in those ionic solids where there is a considerable ...

Consider $3$ crystals (all having FCC lattice) labelled as $\text{P, Q}$ and $\text{R}$ as described below:Crystal $\text{P}$: Cu crystal with $4$ $\text{Cu}$ atoms per u...

​​​​The figure below shows a plane $\text{PQR}$ in a unit cell. The Miller indices of the plane $\text{PQR}$ is$(432)$$(43 \overline{2})$$(23 \overline{4})$$(\overline{2}...

​​​​​There is $\textsf{NO}$ base-centered cubic lattice among the list of $14$ Bravais lattices because of one or more of the following reasonsIt does $\textsf{NOT}$ have...

In an $\textsf{FCC}$ crystal with lattice parameter $a$, consider the reaction of two leading partial dislocations, $\text{AB}$ and $\text{CD}$, at the line of intersecti...

For a pure element with a $\textsf{BCC}$ crystal structure, the surface energies per unit area of $\{100\}$ and $\{110\}$ free surfaces are $S_{100}$ and $S_{110}$, respe...

Which one of the following unit cell parameters represents a tetragonal crystal system?$\mathrm{a}=\mathrm{b}=\mathrm{c} ; \quad \alpha=\beta=\gamma \neq 90^{\circ}$$\mat...

The Miller indices for the shaded plane shown in the unit cell below is $[632]$$[123]$$(632)$$(123)$

Which of the following figures schematically represent(s) either the Frenkel defect or the Schotky defect in ionic solids?

\begin{tabular}{|l|l|}\hline Q.48 & \begin{tabular}{l}Aliovalent doping of $M g C l_{2}$ in $\mathrm{NaCl}$ leads to the formation of defects. Which one \\of the followin...

\begin{tabular}{l|l}Q. 49 & \begin{tabular}{l}A screw dislocation in a FCC crystal has Burgers vector of $\frac{a}{2}[110]$, where $a$ is the \\lattice constant. The poss...

Q. 51 A metal has a certain vacancy fraction at a temperature of $600 \mathrm{~K}$. On increasing the temperature to $900 \mathrm{~K}$, the vacancy fraction increases by ...

\begin{tabular}{|l|l|}\hline Q. 53 & \begin{tabular}{l}A student performed X-ray diffraction experiment on a FCC polycrystalline pure \\metal. The following $\sin ^{2} \t...

\begin{tabular}{|c|c|c|}\hline \multirow[t]{6}{*}{ Q. 55} & \multicolumn{2}{|c|}{ Match the hardness test (in Column I) with its indenter type (in Column II). } \\\hline ...

\begin{tabular}{|l|l|}\hline Q. 58 & \begin{tabular}{l}Among the 14 Bravais lattices, there is no base centred cubic unit cell. Which of \\the following statement(s) is/a...

\begin{tabular}{|l|l|}\hline Q.44 & Number of atoms per unit area of the (110) plane of a body centered cubic crystal, \\with lattice parameter ' $a$ ', is \\\hline& $\fr...

Q.45 Match the following materials with their corresponding bonding types.$\mathrm{P}-4 ; \mathrm{Q}-2 ; \mathrm{R}-3 ; \mathrm{S}-1$$\mathrm{P}-3 ; \mathrm{Q}-4 ; \mathr...

The enthalpy required to create an oxygen vacancy in $\mathrm{CeO}_2$ is $4 \mathrm{eV}$. The number of oxygen vacancies present per mole of $\mathrm{CeO}_2$ at $1000 \ma...

A two-phase $(\alpha+\beta)$ mixture of an $\text{A-B}$ binary system has the following properties:Phase $\alpha$ has equal weight percentages of $\mathrm{A}$ and $\mathr...

A spherical $\beta$ particle nucleates from the $\alpha$ matrix on a non-deformable substrate \end{tabular} $\delta$, forming a contact angle of $\theta$ as shown in the ...